Question

question 13 (4 points)
what must human embryos possess in order to be viable?
at least one x chromosome
two y chromosomes
at least one y chromosome
three y chromosomes
question 14 (4 points)
researchers have found that diet, tobacco, and lack of sleep may affect______
through the process of methylation, which can contribute to depression, obesity, and
various forms of cancer.
gene behavior
meiosis
mitosis
forethought

Explanation:

Question 13

To determine what human embryos must possess to be viable, we analyze the options:

• Human embryos need at least one X chromosome for viability. Females have XX, males have XY. Embryos without an X chromosome (e.g., with only Y or multiple Ys without X) are not viable. Two Y chromosomes or three Y chromosomes are not viable as they lack the necessary X - related genetic material. And an embryo doesn't need a Y chromosome (females don't have Y chromosomes). So the correct option is "at least one X chromosome".

Methylation is a process that affects gene behavior (gene expression). Meiosis is cell division for gamete production, mitosis is for cell growth/repair, and forethought is a cognitive concept. Diet, tobacco, and lack of sleep affect gene behavior via methylation, leading to conditions like depression, obesity, and cancer. So the correct option is "gene behavior".

Answer:

A. at least one X chromosome

Question 14